Natural immunity to influenza A and B among Saudi blood donors in Al Madinah Al Munawarah, Saudi Arabia.

OBJECTIVES

To investigate the seroprevalence of influenza viruses (A and B) among blood donors in Kingdom of Saudi Arabia. Methods: The present investigation was conducted between April 2019 and July 2019. Participants were healthy adults recruited from the central blood bank Al Madinah Al Munawarah, Kingdom of Saudi Arabia. Immunoglobulin G (IgG) levels against influenza A and B were measured in serum samples using ELISA.

RESULTS

The results showed that 29.2% of the sample had significant concentrations of influenza A IgG antibody, whereas 38.6% had significant concentrations of influenza B IgG antibody. A strong correlation was found between the levels of influenza A and influenza B antibodies (r=0.708, p less than 0.001). The number of individuals identified as negative for influenza A IgG antibody increased with age (p less than 0.01). In addition, no correlations were identified between influenza A IgG and influenza B IgG and body mass index (BMI), (p greater than 0.05). Finally, linear regression analysis showed that the level of influenza A antibody can be predicted by age (p less than 0.05) and body mass index (BMI) (p less than 0.05).

CONCLUSION

Approximately one-third of Saudi Arabian adults presented significant levels of influenza A and B antibodies in our study. Demographic factors, including age and BMI, might contribute to influenza A antibody levels.